Smith-based EDA method for gradual transmission lines and related apparatus

Abstract

An EDA method, device and equipment based on Smith gradual transmission line, the scheme firstly acquires the matching path on the Smith circle diagram, discretizes the matching path, then adopts the generalized reflection coefficient circle to fit the discretized matching path, determines the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path, finally cascades the characteristic impedance and electrical length of the transmission line corresponding to each generalized reflection coefficient circle obtained by fitting, takes the cascaded result as the gradual transmission line and outputs. In the scheme, the calculation mode of the transmission line is realized based on the Smith circle diagram, and the Smith circle diagram can be easily constructed in the EDA design tool, which greatly facilitates the design work of the technical personnel.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically to an EDA method and related equipment based on Smith's gradient transmission lines. Background Technology

[0002] Smith charts are widely used tools for matching circuit design and impedance transformation applications. In the design process, tapered transmission lines are suitable for broadband impedance matching or impedance transformation applications in RF and microwave circuits. Existing main synthesis methods synthesize these tapered transmission lines using formulas or numerical algorithms. These methods share common drawbacks: they are limited to impedance transformation between real impedances; they lack flexibility and cannot easily optimize the tapered line locally according to the needs of actual circuits; and they are not intuitive or convenient when combining multiple matching techniques (such as simultaneously using lumped and distributed parameter components). Summary of the Invention

[0003] In view of this, embodiments of the present invention provide an EDA method and apparatus for gradient transmission lines based on Smith, so as to achieve rapid and flexible design of gradient lines.

[0004] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0005] An EDA method based on Smith's graded transmission line includes:

[0006] Obtain the matching path on the Smith chart and discretize the matching path;

[0007] The discretized matching path is fitted using a generalized reflection coefficient circle.

[0008] The characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle are determined based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path.

[0009] The characteristic impedance and electrical length of the transmission lines corresponding to the various generalized reflection coefficient circles obtained by fitting are cascaded, and the cascaded result is used as a graded transmission line and output.

[0010] Optionally, in the above EDA method based on Smith's gradient transmission line, the matching path is discretized, including:

[0011] N discrete points are set on the matching path, where N is a positive integer not less than 2.

[0012] Optionally, in the above EDA method based on Smith's graded transmission line, the discretized matching path is fitted with a generalized reflection coefficient circle, including:

[0013] Choose the matching path after discretization of the generalized reflection coefficient circular fitting;

[0014] The intersection point of the selected generalized reflection coefficient circle and the matching path is a discrete point on the matching path, and the center of the generalized reflection coefficient circle is located on the real axis of the Smith chart.

[0015] Optionally, in the above EDA method based on Smith's graded transmission line, the selection of the matching path after discretization of the generalized reflection coefficient circle fitting includes:

[0016] Select two discrete points on the discretized matching path in sequence, wherein the two selected discrete points are adjacent, and one of the two currently selected discrete points is contained in the two previously selected discrete points;

[0017] Obtain a generalized reflection coefficient circle that is adapted to the two selected discrete points and fit the two selected discrete points so that the center of the obtained generalized reflection coefficient circle is located on the real axis of the Smith chart, and the intersection of the obtained generalized reflection coefficient circle and the matching path is the two selected discrete points.

[0018] Optionally, in the above EDA method for graded transmission lines based on Smith, determining the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each fitted generalized reflection coefficient circle and the intersection of the generalized reflection coefficient circle and the matching path includes:

[0019] The radius of the generalized reflection coefficient circle is calculated based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle with the matching path.

[0020] Based on formula The load impedance z is calculated. l , where x c R represents the x-coordinate of the circle of generalized reflection coefficient, and R represents the radius of the circle of generalized reflection coefficient.

[0021] Based on formula The characteristic impedance z of the transmission line is calculated. c ;

[0022] To obtain the reflection coefficient of the generalized reflection coefficient circle;

[0023] Based on the reflection coefficient and load impedance z l Characteristic impedance z c The electrical length of the transmission line is calculated.

[0024] Optionally, in the above EDA method based on Smith's graded transmission line, based on the reflection coefficient and load impedance z... l Characteristic impedance z c The electrical length of the transmission line is calculated, including:

[0025] For the formula Solve the problem to calculate the first electrical length βl1 and the second point length βl2;

[0026] The difference between the second point length βl2 and the first electrical length βl1 is taken as the electrical length of the transmission line;

[0027] Where j is a pure imaginary number with an amplitude of 1.

[0028] Optionally, in the above-mentioned EDA method based on Smith's graded transmission line, the step of cascading the characteristic impedance and electrical length of the transmission line corresponding to each fitted generalized reflection coefficient circle, and outputting the cascaded result as a graded transmission line, includes:

[0029] The characteristic impedance and electrical length of the transmission line corresponding to each of the fitted generalized reflection coefficient circles are cascaded.

[0030] Smooth the cascaded results;

[0031] The smoothed cascaded result is output as a gradient transmission line.

[0032] An EDA device based on Smith's graded transmission line includes:

[0033] A discretization unit is used to obtain the matching path on the Smith chart and to discretize the matching path.

[0034] Matching unit, used to fit the discretized matching path using a generalized reflection coefficient circle;

[0035] The processing unit is used to determine the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path.

[0036] The output unit is used to cascade the characteristic impedance and electrical length of the transmission lines corresponding to the various generalized reflection coefficient circles obtained by fitting, and output the cascaded result as a graded transmission line.

[0037] Optionally, in the EDA device for the gradient transmission line of the Smith chart described above, the matching unit is specifically used for:

[0038] Choose the matching path after discretization of the generalized reflection coefficient circular fitting;

[0039] The intersection point of the selected generalized reflection coefficient circle and the matching path is a discrete point on the matching path, and the center of the generalized reflection coefficient circle is located on the real axis of the Smith chart.

[0040] Optionally, in the above-mentioned EDA device for the gradient transmission line of the Smith chart, the matching unit, in selecting the matching path after the discretization of the generalized reflection coefficient circle fitting, is specifically used for:

[0041] Select two discrete points on the discretized matching path in sequence, wherein the two selected discrete points are adjacent, and one of the two currently selected discrete points is contained in the two previously selected discrete points;

[0042] Obtain a generalized reflection coefficient circle that is adapted to the two selected discrete points and fit the two selected discrete points so that the center of the obtained generalized reflection coefficient circle is located on the real axis of the Smith chart, and the intersection of the obtained generalized reflection coefficient circle and the matching path is the two selected discrete points.

[0043] An EDA device based on Smith's gradient transmission line includes: a memory and a processor;

[0044] The memory is used to store programs;

[0045] The processor is configured to execute the program to implement each step of the EDA method based on Smith's gradient transmission line as described above.

[0046] Based on the above technical solution, the solution provided in this embodiment of the invention first obtains the matching path on the Smith chart, discretizes the matching path, then fits the discretized matching path with a generalized reflection coefficient circle, and then determines the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each fitted generalized reflection coefficient circle and the intersection of the generalized reflection coefficient circle and the matching path. Finally, the characteristic impedance and electrical length of the transmission line corresponding to each fitted generalized reflection coefficient circle are cascaded, and the cascaded result is output as a graded transmission line. The transmission line calculation method in this solution is based on the Smith chart, which can be easily constructed in EDA and other design tools. Therefore, the technical solution disclosed in this application can be easily integrated into various existing EDA and other design tools, greatly facilitating the design work of technical personnel. Furthermore, during design, the required characteristic impedance value can be selected as needed. This method is flexible and can realize the transformation between real impedances and the transformation between complex impedances. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0048] Figure 1 This is a flowchart illustrating the EDA method based on Smith's gradient transmission line disclosed in an embodiment of this application.

[0049] Figure 2 This is a schematic diagram of the generalized reflection coefficient circle constructed on the Smith chart as disclosed in the embodiments of this application;

[0050] Figure 3 This is a schematic diagram illustrating the smoothing effect of a gradient transmission line.

[0051] Figure 4 This is a schematic diagram of the microstrip line designed using the proposed scheme.

[0052] Figure 5 This is a schematic diagram of the load circuit.

[0053] Figure 6 This is a schematic diagram of the generalized reflection coefficient circle constructed on the Smith chart as disclosed in the embodiments of this application;

[0054] Figure 7 This is a schematic diagram of a generalized reflection coefficient circle constructed on a Smith chart, as disclosed in another embodiment of this application;

[0055] Figure 8 This is a schematic diagram of the structure of the EDA device based on Smith's gradient transmission line disclosed in an embodiment of this application;

[0056] Figure 9 This is a schematic diagram of the structure of the EDA device based on Smith's gradient transmission line disclosed in an embodiment of this application. Detailed Implementation

[0057] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] This application provides a gradient transmission line design method, see [link to related document]. Figure 1 The method may include:

[0059] Step S101: Obtain the matching path on the Smith chart and discretize the matching path.

[0060] In this step, the matching path on the Smith chart is discretized. The matching path is... Figure 2 The line segment Γ(x,y) in the diagram represents the matching path. This step involves discretizing the matching path Γ(x,y) by setting N discrete points on the path, where N is a positive integer not less than 2. For example... Figure 2 The discrete points on the matching path shown may include Γ0, Γ1, Γ2, Γ N-1 .

[0061] Step S102: Use the generalized reflection coefficient circle to fit the discretized matching path.

[0062] In this step, multiple generalized reflection coefficient circles are selected to fit the discretized matching path. The center of each selected generalized reflection coefficient circle lies on the real axis of the Smith chart, and the generalized reflection coefficient circle intersects the matching path at two points. This process is equivalent to fitting the discretized matching path using generalized reflection coefficient circles. Furthermore, the intersection points of the generalized reflection coefficient circles and the matching path are the discrete points configured on the matching path in step S101 above; that is, the intersection points of the selected generalized reflection coefficient circles and the matching path are discrete points on the matching path.

[0063] In this step, two adjacent discrete points can be selected sequentially from the matching path of the discretization process. One of the currently selected discrete points is contained within the two previously selected discrete points. A generalized reflection coefficient circle adapted to fit the two selected discrete points is obtained and fitted to them. This is done so that the center of the obtained generalized reflection coefficient circle lies on the real axis of the Smith chart, and the intersection of the obtained generalized reflection coefficient circle and the matching path is the two selected discrete points. Once the generalized reflection coefficient circle is determined, its diameter is also determined.

[0064] The fitting results can be found in Figure 2 As shown, Figure 2 In the diagram, GRCC1, GRCC2, and GRCC3 are the generalized reflection coefficient circles.

[0065] Step S103: Based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path, determine the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle.

[0066] Once the generalized reflection coefficient circle is determined, the center coordinates of each selected generalized reflection coefficient circle and the intersection coordinates with the matching path can be extracted. Based on the center coordinates and intersection coordinates, the characteristic impedance and electrical length of the transmission line segment fitted by the generalized reflection coefficient circle can be determined.

[0067] Step S104: Concatenate the characteristic impedance and electrical length of the transmission lines corresponding to the fitted generalized reflection coefficient circles, and output the cascaded result as a graded transmission line.

[0068] Each selected generalized reflection coefficient circle corresponds to a transmission line segment. The characteristic impedance and electrical length of each transmission line segment can be calculated through step S103. The characteristic impedance and electrical length of these transmission lines are cascaded, and the cascaded result is used as a gradient transmission line and output.

[0069] Furthermore, in this embodiment, since the gradient transmission line is composed of multiple transmission line segments, each with different characteristic impedances and electrical lengths, to ensure a smooth transition, this solution involves cascading the characteristic impedances and electrical lengths of the transmission lines corresponding to the fitted generalized reflection coefficient circles, and outputting the cascaded result as the gradient transmission line. Specifically, this includes: cascading the characteristic impedances and electrical lengths of the transmission lines corresponding to the fitted generalized reflection coefficient circles; smoothing the cascaded result; and outputting the smoothed cascaded result as the gradient transmission line. The cascaded result can be found in [reference needed]. Figure 3 As shown, Figure 3 The horizontal axis represents the length of the transmission line, and the vertical axis represents the width of the tapered transmission line. The width of the tapered transmission line corresponds to its characteristic impedance, and there is a specific mapping relationship between the two. Once the characteristic impedance of the transmission line is determined, the width of the transmission line is also determined. The output results for the tapered transmission line can be found in [reference needed]. Figure 4 As shown.

[0070] Calculations regarding the characteristic impedance and electrical length of transmission lines:

[0071] See Figure 5 , Figure 5 The diagram shows the equivalent circuit of a load passing through a transmission line. From this circuit diagram, the characteristic parameters j and Z of the circuit can be extracted. c , β, and Z l Where j is a pure imaginary number with an amplitude of 1, Z c The characteristic impedance of the transmission line is given by β, the wavelength number (equal to 2π divided by the wavelength of the electromagnetic wave in the medium), and l is the electrical length of the transmission line. l Given the load impedance, calculate the characteristic impedance of each target circuit based on the aforementioned characteristic parameters.

[0072] Specifically, after obtaining the aforementioned characteristic parameters, it is possible to base them on the formula. The input impedance z corresponding to the characteristic parameter is calculated. in ;

[0073] The reflection coefficient that matches this input impedance is:

[0074] The Γ x and Γ y These are the x and y coordinates of a point on the matching path, respectively.

[0075] Right now, This formula can be defined as the reflection coefficient formula;

[0076] See Generalized Reflection Coefficient Circle (GRCC) Figure 2 , Figure 6 and Figure 7 As shown in the figure (x) i-1 y i-1 ), (x i y i ), where x and y are the coordinates of two discrete points on the matching path. ci Let βl1 be the coordinates of the center of the circle (x1, y1), βl2 be the length of the point corresponding to the coordinate point (x2, y2) on the GRCC, and βl1 be the length of the point corresponding to the coordinate point (x2, y2) on the GRCC.

[0077] As φ increases, the reflection coefficient Γ shifts clockwise on the Smith chart. Once the GRCC is obtained (i.e., the center and radius of the GRCC are known), z can be calculated using the reflection coefficient formula. l and z c (Let βl = 0 and ) ):

[0078]

[0079] Then, using the reflection coefficient formula, the electric lengths βl1 and βl2 corresponding to the two reflection coefficient points are obtained. Therefore, the electric length between the two reflection coefficient points is the difference between them.

[0080] Δβl=βl2-βl1

[0081] Once the characteristic impedance and electrical length of the transmission line are obtained, the physical width and length of the transmission line in the circuit board can be determined.

[0082] Therefore, in the above scheme, determining the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path includes:

[0083] The radius of the generalized reflection coefficient circle is calculated based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle with the matching path.

[0084] Based on formula The load impedance z is calculated. l , where x c R represents the x-coordinate of the circle of generalized reflection coefficient, and R represents the radius of the circle of generalized reflection coefficient.

[0085] Based on formula The characteristic impedance z of the transmission line is calculated. c ;

[0086] To obtain the reflection coefficient of the generalized reflection coefficient circle;

[0087] Based on the reflection coefficient and load impedance z l Characteristic impedance z c The electrical length of the transmission line is calculated.

[0088] Based on the reflection coefficient and load impedance z l Characteristic impedance z c The electrical length of the transmission line is calculated, including:

[0089] For the formula Solve the problem to calculate the first electrical length βl1 and the second point length βl2;

[0090] The difference between the second point length βl2 and the first electrical length βl1 is taken as the electrical length of the transmission line;

[0091] Where j is a pure imaginary number with an amplitude of 1.

[0092] This embodiment also discloses an EDA device based on Smith's gradient transmission line. For the specific working content of each unit in the device, please refer to the content of the above method embodiment. The EDA device based on Smith's gradient transmission line provided in this embodiment of the invention will be described below. The EDA device based on Smith's gradient transmission line described below and the EDA method based on Smith's gradient transmission line described above can be referred to in correspondence.

[0093] See Figure 8 The EDA device based on Smith's gradient transmission line disclosed in this application includes:

[0094] Discretization unit A is used to obtain the matching path on the Smith chart and discretize the matching path;

[0095] Matching unit B is used to fit the discretized matching path using a generalized reflection coefficient circle.

[0096] Processing unit C is used to determine the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path.

[0097] Output unit D is used to cascade the characteristic impedance and electrical length of the transmission lines corresponding to the various generalized reflection coefficient circles obtained by fitting, and output the cascaded result as a graded transmission line.

[0098] The specific working processes of the discretization unit A, matching unit B, processing unit C, and output unit D are described in the above method embodiments and will not be repeated here.

[0099] Figure 9 The hardware structure diagram of the EDA device with a gradient transmission line based on the Smith chart provided in this embodiment of the invention is shown below. Figure 9 As shown, it may include: at least one processor 100, at least one communication interface 200, at least one memory 300 and at least one communication bus 400;

[0100] In this embodiment of the invention, the number of processor 100, communication interface 200, memory 300, and communication bus 400 is at least one, and the processor 100, communication interface 200, and memory 300 communicate with each other through communication bus 400; obviously, Figure 9 The communication connections shown for the processor 100, communication interface 200, memory 300, and communication bus 400 are optional.

[0101] Optionally, the communication interface 200 can be an interface of a communication module, such as the interface of a GSM module;

[0102] Processor 100 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0103] The memory 300 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0104] Specifically, processor 100 is used for:

[0105] Obtain the matching path on the Smith chart and discretize the matching path;

[0106] The discretized matching path is fitted using a generalized reflection coefficient circle.

[0107] The characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle are determined based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path.

[0108] The characteristic impedance and electrical length of the transmission lines corresponding to the various generalized reflection coefficient circles obtained by fitting are cascaded, and the cascaded result is used as a graded transmission line and output.

[0109] Smith charts are widely used tools for matching circuit design and impedance transformation applications. As seen in the above scheme, this invention proposes an EDA scheme based on Smith's tapered transmission lines. This scheme can not only perform matching design between real impedances but also conveniently match between complex impedances. Furthermore, it operates directly on the Smith chart, making circuit design more intuitive and convenient, and facilitating integration into EDA tools, thereby improving the design efficiency of engineers. Because this algorithm is based on the Smith chart, it can be easily integrated into various existing EDA design tools, greatly facilitating the design work of engineers. This method is flexible in design, capable of transforming between both real and complex impedances.

[0110] For ease of description, the above system is described by dividing it into various modules based on their functions. Of course, in implementing this invention, the functions of each module can be implemented in one or more software and / or hardware components.

[0111] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0112] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0113] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0114] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0115] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An EDA method based on Smith's graded transmission lines, characterized in that, include: Obtain the matching path on the Smith chart and discretize the matching path; Two discrete points on the matching path after fitting the discretized generalized reflection coefficient circle are selected sequentially. The two selected discrete points are adjacent, and one of the currently selected discrete points is contained in the two previously selected discrete points. The generalized reflection coefficient circle adapted to the two selected discrete points is fitted and matched so that the center of the obtained generalized reflection coefficient circle is located on the real axis of the Smith chart, and the intersection of the obtained generalized reflection coefficient circle and the matching path is the two selected discrete points. The characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle are determined based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path. The characteristic impedance and electrical length of the transmission lines corresponding to the various generalized reflection coefficient circles obtained by fitting are cascaded, and the cascaded result is used as a graded transmission line and output.

2. The EDA method based on Smith's graded transmission line according to claim 1, characterized in that, Discretizing the matching path includes: N discrete points are set on the matching path, where N is a positive integer not less than 2.

3. The EDA method based on Smith's graded transmission line according to claim 1, characterized in that, The determination of the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path includes: The radius of the generalized reflection coefficient circle is calculated based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle with the matching path. Based on formula The load impedance was calculated. ,in R represents the x-coordinate of the circle of generalized reflection coefficient, and R represents the radius of the circle of generalized reflection coefficient. Based on formula The characteristic impedance of the transmission line is calculated. ; To obtain the reflection coefficient of the generalized reflection coefficient circle; Based on the reflection coefficient and load impedance Characteristic impedance The electrical length of the transmission line is calculated.

4. The EDA method based on Smith's graded transmission line according to claim 3, characterized in that, Based on the reflection coefficient and load impedance Characteristic impedance The electrical length of the transmission line is calculated, including: For the formula Solve the problem and calculate the first electrical length. Second electrical length ; The second electrical length With the first electrical length The difference is taken as the electrical length of the transmission line; Where j is a pure imaginary number with an amplitude of 1.

5. The EDA method based on Smith's graded transmission line according to claim 1, characterized in that, The process of cascading the characteristic impedance and electrical length of the transmission lines corresponding to the fitted generalized reflection coefficient circles, and outputting the cascaded result as a graded transmission line, includes: The characteristic impedance and electrical length of the transmission line corresponding to each of the fitted generalized reflection coefficient circles are cascaded. Smooth the cascaded results; The smoothed cascaded result is output as a gradient transmission line.

6. An EDA device based on Smith's graded transmission line, characterized in that, include: A discretization unit is used to obtain the matching path on the Smith chart and to discretize the matching path. Matching unit, used to fit the discretized matching path using a generalized reflection coefficient circle; The processing unit is used to determine the characteristic impedance and electrical length of the transmission line corresponding to the generalized reflection coefficient circle based on the center coordinates of each generalized reflection coefficient circle obtained by fitting and the intersection of the generalized reflection coefficient circle and the matching path. The output unit is used to cascade the characteristic impedance and electrical length of the transmission line corresponding to each of the fitted generalized reflection coefficient circles, and output the cascaded result as a graded transmission line. Specifically, the matching unit is used for: Two discrete points on the matching path after fitting the discretized generalized reflection coefficient circle are selected sequentially. The two selected discrete points are adjacent, and one of the currently selected discrete points is contained in the two previously selected discrete points. The generalized reflection coefficient circle adapted to the two selected discrete points is fitted and matched so that the center of the obtained generalized reflection coefficient circle is located on the real axis of the Smith chart, and the intersection of the obtained generalized reflection coefficient circle and the matching path is the two selected discrete points.

7. An EDA device based on Smith's graded transmission line, characterized in that, include: Memory and processor; The memory is used to store programs; The processor is configured to execute the program to implement the various steps of the EDA method based on Smith gradient transmission lines as described in any one of claims 1-5.

Images